In the semiconductor industry, various manufacturing processes are typically carried out on a substrate (e.g., a semiconductor wafer) in order to achieve various results thereon. Processes such as ion implantation, for example, can be performed in order to obtain a particular characteristic on or within the substrate, such as limiting a diffusivity of a dielectric layer on the substrate by implanting a specific type of ion. Conventionally, ion implantation processes are performed in either a batch process, wherein multiple substrates are processed concurrently, or a serial process, wherein a single substrate is individually processed. Traditional high-energy or high-current batch ion implanters, for example, are operable to achieve a short ion beam line, wherein a large number of wafers may be placed on a wheel or disk, and the wheel is spun and radially translated through the ion beam, thus exposing all of the substrates surface area to the beam at various times throughout the process. Processing batches of substrates in such a manner, however, generally makes the ion implanter substantially large in size.
In a typical serial process, on the other hand, either an ion beam is scanned in a single axis across a stationary wafer, or the wafer is translated in one direction past a fan-shaped or scanned ion beam. The process of scanning or shaping a uniform ion beam, however, generally requires a complex and/or long beam line, which is generally undesirable at low energies. Furthermore, a uniform translation and/or rotation of either the ion beam or the wafer is generally required in order to provide a uniform ion implantation across the wafer. The relative motion of beam and wafer in translation and/or rotation can be achieved in such manner that the whole surface area of the wafer is implanted with specific ions in a uniform manner. This relative scanning motion can be achieved by mechanical scanning of the wafer through a stationary ion beam, scanning the beam across a relatively stationary wafer, or a combination of scanning both the wafer and the ion beam. In the case of a non-scanned or stationary ion beam, mechanical motion of the wafer should happen in two generally orthogonal axes, wherein the whole wafer surface area is covered by the spot beam by a uniform translation of the wafer along the axes. However, such a uniform translation and/or rotation has been difficult to achieve, due, at least in part, to substantial inertial forces associated with moving the conventional devices and scan mechanisms during processing.
Therefore, a need exists for a device for scanning an ion beam across a substrate, wherein the substrate is uniformly translated and/or rotated with respect to the ion beam.